1. Field of the Invention
The invention relates in general to elevator systems, and more specifically to door operator and door mounting arrangements for the elevator car of an elevator system in which the car frame of the elevator car is disposed adjacent to the car front.
2. Description of the Prior Art
Concurrently filed Application Ser. No. 219,103, entitled "Elevator System" discloses a low cost hydraulic elevator system suitable for low rise buildings. A substantial portion of the cost savings in this elevator system is the elimination of the drilled hole by extending the hydraulic jack upwardly through the elevator car via a tunnel structure which may also provide the primary vertical structural member of the car frame. Disposing this tunnel, and also the car frame at the front of the elevator car, enables the tunnel to be enclosed and concealed between the cr entranceway and the car mounted operational controls.
The tunnel, which in most instances will extend through and above the top beam of the car frame, poses a problem in the utilization of some types of door operators, as well as a problem in mounting the car door, or doors. Further, the door operator is a relatively heavy apparatus, and one of the objectives of the low cost hydraulic elevator system was to reduce weight, which in turn reduces the size and cost of the hydraulic power unit required. Further, the door operators of the prior art, being disposed on the top of the elevator car, require maintenance personnel to gain access to the car top, and this mounting arrngement also requires the additional expense of a car top station for use by the maintenance personnel. Another objective of the low cost hydraulic elevator system was to make all car mounted operational controls, as well as hatch mounted switches, accessible from within the elevator car, or from a hatchway entrance.
Thus, it would be desirable to provide a new and improved elevator system having a door operator, and door mounting means which will operate with the front tunnel/front car frame construction; it would be desirable to reduce the weight of such a door operator; and, it would further be desirable to make the door operator accessible for maintenance from within the elevator car, making it unnecessary for maintenance personnel to gain access to the top of the elevator car.